ensure Google Analytics is properly wired to H.

## Bug report form
### Steps to reproduce
1. Log in to Google Analytics for H.
2. See this message:

The default URL https://hypothes.is, for property UA-26026798-5 has no tracking code for this property, although it does have tracking codes for other properties:

UA-26026798-8

If your Tracking ID and your Default URL setting are out of sync, you don’t get valid data in your Analytics account for the Default URL.

Either update the tracking code to use the Tracking ID for property Client, or open the Property Settings to update the Default URL for property Client to be https://hypothes.is.

Google Tag Assistant Recordings can help you ensure that your default URL is tagged for the correct properties.

### Expected behavior
I don't know enough about how GA is wired to the H. client and servers, but we should make sure we have GA wired up as necessary to collect the data we want to collect.

Start by reviewing how Google Analytics is wired to the Hypothesis client and servers, then compare that setup with the reported property UA-26026798-5, tracking ID UA-26026798-8, and default URL https://hypothes.is. Done means the relevant tracking configuration is aligned and the data Hypothesis intends to collect is confirmed.

Written by the indexing model from the issue text.